The alluvial fan would be enough to convince me I think... if it exists but shouldn't exist based on their theory. NAU has / puts out some decent geologists, archeologists and paleontologists who tend to be thorough if not somewhat conservative. At least as far as I can tell based on some of the literature they have produced and visits to the Museum in FLG.

No. This is how real science gets done; somebody presents a real, testable hypothesis based on actual data, and then submits it for review to see if they've got it wrong. If it turns out that it is wrong, then the other scientists will point that out, and the scientist who proposed it will go back to the drawing board. If it turns out that we can't find anything wrong with it, the consensus will change.

Denialists skip this process, and just say that the consensus is wrong without any good data to back up their competing hypothesis, if they even have one.

No. This is how real science gets done; somebody presents a real, testable hypothesis based on actual data, and then submits it for review to see if they've got it wrong. If it turns out that it is wrong, then the other scientists will point that out, and the scientist who proposed it will go back to the drawing board. If it turns out that we can't find anything wrong with it, the consensus will change.

Agreed. Time will tell.

That's how we went from "global warming" (circa 2004) to "climate change" (circa 2012), when it was seen that oops temps weren't increasing.

Anyway, back to the canyons, Flowers et al may be on groundbreaking territory just like J Harlen Bretz was with regard to the Columbia River Gorge canyons in the 1920s. Let's see what develops.

That's how we went from "global warming" (circa 2004) to "climate change" (circa 2012), when it was seen that oops temps weren't increasing.

Don't you ever get tired of being dead wrong? When you want to play these desperate cries for attention, why don't you keep your fake history to the climate threads instead of crapping all over these other science articles where the most bullshit we expect is the token Young Earthers every once in a while? Nobody here wants to deal with your bullshit.

No. This is how real science gets done; somebody presents a real, testable hypothesis based on actual data, and then submits it for review to see if they've got it wrong. If it turns out that it is wrong, then the other scientists will point that out, and the scientist who proposed it will go back to the drawing board. If it turns out that we can't find anything wrong with it, the consensus will change.

Denialists skip this process, and just say that the consensus is wrong without any good data to back up their competing hypothesis, if they even have one.

Well this is all good as another comment mentioned, that this causes everyone to think about their findings a little more and to analyze one another's measurements and calculations... in the end we win.

No. This is how real science gets done; somebody presents a real, testable hypothesis based on actual data, and then submits it for review to see if they've got it wrong. If it turns out that it is wrong, then the other scientists will point that out, and the scientist who proposed it will go back to the drawing board. If it turns out that we can't find anything wrong with it, the consensus will change.

Denialists skip this process, and just say that the consensus is wrong without any good data to back up their competing hypothesis, if they even have one.

All this polite scientific dialog back and forth, bah! What ever happened to gentlemen fighting duels to resolve their differences?

Alas! but we had to move on from duel fighting when those ladies started meddling with the Gentleman's own province of science, since of course a gentleman cannot fight a lady and so was doomed to lose all such contests, or at the least to learn to defend his position with reasoned evidence...

All this polite scientific dialog back and forth, bah! What ever happened to gentlemen fighting duels to resolve their differences?

Alas! but we had to move on from duel fighting when those ladies started meddling with the Gentleman's own province of science, since of course a gentleman cannot fight a lady and so was doomed to lose all such contests, or at the least to learn to defend his position with reasoned evidence...

How sexist! A progressive gentleman would not hesitate to gun down a lady with whom he had a serious dispute.

All this polite scientific dialog back and forth, bah! What ever happened to gentlemen fighting duels to resolve their differences?

Alas! but we had to move on from duel fighting when those ladies started meddling with the Gentleman's own province of science, since of course a gentleman cannot fight a lady and so was doomed to lose all such contests, or at the least to learn to defend his position with reasoned evidence...

How sexist! A progressive gentleman would not hesitate to gun down a lady with whom he had a serious dispute.

My dear fellow, that's a very sound point! Ipso facto any woman who pursues a dispute beyond the bounds of decorum rather than resorting to an embarrassed titter or a dainty blush can be no lady at all. We need feel no compunction should stern resorts be required to adequately rebuke a harridan - in fact her better bred sisters would surely thank us for it!

Hmm. I know almost zit about any of this -but wouldn't the vertical height of the iridium (65MY asteroid impact residue) layer offer a compelling clue? And how about trapped atmospheric composition in the layers? Couldn't that be used to peg the ages of the strata?

Hmm. I know almost zit about any of this -but wouldn't the vertical height of the iridium (65MY asteroid impact residue) layer offer a compelling clue? And how about trapped atmospheric composition in the layers? Couldn't that be used to peg the ages of the strata?

It's not the ages of the rock that's in question, it's when they were cut through by flowing rivers. How old is the "canyon" part of the Grand Canyon?

That's how we went from "global warming" (circa 2004) to "climate change" (circa 2012), when it was seen that oops temps weren't increasing.

Quote:

Anyway, back to the canyons, Flowers et al may be on groundbreaking territory just like J Harlen Bretz was with regard to the Columbia River Gorge canyons in the 1920s. Let's see what develops.

I realize I could read the papers involved, but I'm lazy and not all that bright. How much uplift occurs over 60+ million years, and how would that have affected the path of the Colorado (or the ancient rivers that allegedly carved the western section)?

Serendipitously, teh wife and I are planning to spend a few days at the southern rim of the Grand Canyon in September (assuming sequestration doesn't shut the park down completely). Any particular features I should look for that relate to this story in particular (says the non-geologist)?

I realize I could read the papers involved, but I'm lazy and not all that bright. How much uplift occurs over 60+ million years, and how would that have affected the path of the Colorado (or the ancient rivers that allegedly carved the western section)?

Depends on the place, but there, a fair amount. Enough that the ancient river in question might have flowed the opposite direction.

Quote:

Serendipitously, teh wife and I are planning to spend a few days at the southern rim of the Grand Canyon in September (assuming sequestration doesn't shut the park down completely). Any particular features I should look for that relate to this story in particular (says the non-geologist)?

Don't think so, really, but the sediment deposited in the valley bottom at the mouth (exit) of the canyon is a focal point for the "young-carvers".

Would not the draining of the massive lakes formed by the melting glaciers from the multiple ice ages that have occurred over the past 60+mm years pretty much flush away any normal alluvial fan that might have been there then?

Methinks the core samples from the alluvial fan, as referenced by Tuishimi, might shed some scientific light on this conundrum.

This could be problematic given that the mixing, thus dilution of the western portion, of the eroded material would be extensive in the deposited fan. Maybe trying to estimate based on total volume could get you somewhere? Not sure what the error bars would be on that?